1. Field of the Invention
The invention relates to a casting core for forming a cooling channel.
2. The Prior Art
A soluble casting core for forming a cooling channel in a piston produced using casting technology is known from German Patent Application No. 10 2007 044 105.5, whereby the casting core has a formed-on part for forming an oil supply opening, and another formed-on part for forming the oil drain opening of the cooling channel. The piston undergoes different deformations during engine operation, due to the gas pressure in the combustion chamber, the very high temperatures that prevail in the combustion chamber, and the mechanical stresses of the major thrust side and the minor thrust side of the piston. These deformations lead to great stress in the region between the oil supply opening and the oil drain opening, so that there is the risk of crack formation in this region, if the oil supply opening and the oil drain opening have too small a distance from one another.